Is uncommon to have people in Portugal working less than 40 hours. Tried to find a study to put some numbers in context of the reality I know. In the link Under "Duration of work" you can see that 78.6% of people work either 40 hours or more. http://www.eurofound.europa.eu/observatories/eurwork/compara...
Personally, I've been working for 10+ years and I always follow the 8h. I've pulled extra hours when needed (who hasn't?) but never on a regular basis. In fact, the last 3 companies I've worked for are UK-based and I do 7.5h daily.
(8h work) + (0.5h to 1h lunch break) ~= 9h at the office.
Having said that it's not that difficult to find jobs where the 8h day is generally followed, and work/life balance in general is not bad.
Edit: to clarify a question that appears in other comments, those 8h do not include the lunch break, which is 1h.